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Service bulletin PI 0846

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10083487
Published by NHTSA2016-10-25
Manufacturer's numberPI 0846
Manufacturer's date2014-10-23
NHTSA componentELECTRICAL SYSTEM:SOFTWARE; FUEL SYSTEM, OTHER:STORAGE:FUEL GAUGE SYSTEM

NHTSA's summary

FUEL MANAGEMENT MODULE, REPLACEMENT. ON CERTAIN MACK CNG (COMPRESSED NATURAL GAS) MODELS, BUILT BETWEEN 05/01/2013 AND 07/25/2014, THE LOW FUEL WARNING MAY COME ON TOO EARLY AND THE FUEL GAUGE MAY SHOW FULL IF THE FUEL LEVEL SENSOR SIGNAL BECOMES OPEN. IN ADDITION THE GAUGE MAY SHOW LOWER TANK LEVELS AT COLD TEMPERATURES OR HIGHER TANK LEVELS AT HOTTER TEMPERATURES. THIS IS DUE TO THE FACT THAT THE SOFTWARE IN THE FUEL MANAGEMENT MODULE (FMM) DID NOT HAVE THE CORRECT CALIBRATION, OPEN CIRCUIT FAULT CRITERIA AND WAS NOT TEMPERATURE COMPENSATED.

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Electrical system, Fuel system, Software

Vehicles listed
MACK CXU2014 to 2015

Listing a model year does not mean every vehicle of it is concerned: the document says which.